User Contributed Notes 6 notes

When using prepare to prepare a statement to retrieve LOBs the method order matters.
Also, method 'store_result()' must be called and be called in correct order.
Failure to observe this causes PHP/MySQLi to crash or return an erroneous value.
The proper procedure order is: prepare -> execute -> store_result -> bind -> fetch
The following applies to a Windows SBS server running IIS/6.0 + PHP 5.2.1
MySQL server version 5.0.26-community-nt, client version 5.0.51a

The wording above, in the initial description of the function, can be confusing (quoted below).

"You must call mysqli_stmt_store_result() for every query that successfully produces a result set (SELECT, SHOW, DESCRIBE, EXPLAIN), and only if you want to buffer the complete result set by the client, so that the subsequent mysqli_stmt_fetch() call returns buffered data. "

I had initially understood the part saying "and only if you want to buffer..." to mean that it was only necessary to call this function if you wanted to buffer the result set. This, however, is not the case, and the misunderstanding caused me quite a bit of grief.

So, to clarify for anyone suffering from the same misunderstanding, you ALWAYS must call this function for every query that produces a result set (as listed in the parentheses of the quote above), as far as I can tell.

Lost some hours to find out how to save multirows result of mysqli_stmt to array, when get_result prohibited.Idea, which works is using store_result $stmt=$this->mysqli->prepare("SELECT surname, name, user_id, last_m_own, last_m_str, role FROM users WHERE referer_id=(?)"); $stmt->bind_param('i',$referer_id); $stmt->execute(); $stmt->store_result(); $stmt->bind_result($ans['surname'], $ans['name'], $ans['user_id'], $ans['last_m_own'], $ans['last_m_str'], $ans['role']); $j=$stmt->num_rows; for ($i=0;$i<$j;$i++){ $stmt->data_seek($i); $stmt->fetch(); foreach ($ans as $key=>$value){ $result[$i][$key]=$value; } }Hope will helpful for such newbies as me

Actually, mysqli_stmt_result_metadata() returns FALSE, not NULL, when the query/statement doesn't produce a result set. You would have to check the if the $mysqliObject->error is an empty string to see whether the FALSE return means that the query does not produce a result set or that an error occured.

In response to the note below me for the claim that mysqli_fetch_fields is not compatible with prepared statements.

This is untrue, it is but you have to do a little extra work. I would recommend you use a wrapper function of some sort to take care of the dirty business for you but the basic idea is the same.

Let's assume you have a prepared statement like so. I am going to use the procedural way for simplicity but the same idea can be done using the object oriented way:

<?php

// Connect Blah Blah Blah.

$connectionLink = mysqli_connect( .... );

// Query Blab Blah Blah.

$query = "Select `Id` From `Table` Where `Id` = ?";

// Prepare Query.

$prepareObject = mysqli_prepare( $connectionLink , $query );

// Bind Query.

mysqli_stmt_bind_param( $prepareObject , 'i' , 1 );

// Execute Query.

mysqli_stmt_execute( $prepareObject );

?>

Now all the above is fine and dandy to anyone familiar with using prepared statements, but if I want to use mysqli_fetch_fields or any other function that fetches meta information about a result set but does not work on prepared statements?

Enter the special function mysqli_stmt_result_metadata. It can be used as follows, assume the following code segment immediatley follows that of the above code segment.

<?php

$metaData = mysqli_stmt_result_metadata( $prepareObject );

// I Can Now Call mysqli_fetch_fields using the variable
// $metaData as an argument.

$fieldInfo = mysqli_fetch_fields( $metaData );

// Or Even This.

$fieldInfo = mysqli_num_fields( $metaData );

?>

Take a look at the Manual entry for mysqli_stmt_result_metatdata function for full details on how to expose it with prepared statements.